ajparry89
Junior Member
Doing a rebuild on a 5.7 out of a 2010. Not my first rebuild, nor my first hemi. Along the way, had some miscommunication with my buddy who was helping me, and the piston/rods got mixed up.
We grinder down the carbon and found all the arrows on the pistons, then marked which way they were positioned on the rods, and put the new pistons on the rods the same way they were. It seemed that the difference was, on the rods, here is a slight slight wider shoulder (if that’s what you call it) on one side around the rod bearing. And when keeping all the piston arrows pointing forward, 4 rods have the wider shoulder toward the front, and 4 have it toward the rear - that seems to be the difference between the left and right. Am I right so far?
so I measured the offset, looking down the cylinder, which way the cylinder was slightly off center of the crank journal, and got them correct or what seemed correct. Everything went together great, no issues, spin so nice and freely, I could spin it by hand with all pistons in (no compression) no binding or nothing.
Got it all together, and after about 10-15 seconds of cranking, it locked up. Tore the pan off and the wrist pins are seized in the pistons! Like 3 or 4 of them. Some on each side. But no pattern. Never seen anything like this! Another engine builder looked at it and can’t figure it out either.
Anybody have any idea what could have gone wrong? I’m open to the idea that my rods are on the wrong side? But it just doesn’t seem that way. If switched them, the offset would be too great I think and would bind even tryin to turn by hand.
Anybody have a way of knowing for sure which way the rods are supposed to face?
You don’t have to reply saying I need to mark them. I know that, like I said, a miscommunication. I’ve done hemis before. Looking for some help here, I’m tearing it all back apart now, but want to do it right this time lol. Thanks!
We grinder down the carbon and found all the arrows on the pistons, then marked which way they were positioned on the rods, and put the new pistons on the rods the same way they were. It seemed that the difference was, on the rods, here is a slight slight wider shoulder (if that’s what you call it) on one side around the rod bearing. And when keeping all the piston arrows pointing forward, 4 rods have the wider shoulder toward the front, and 4 have it toward the rear - that seems to be the difference between the left and right. Am I right so far?
so I measured the offset, looking down the cylinder, which way the cylinder was slightly off center of the crank journal, and got them correct or what seemed correct. Everything went together great, no issues, spin so nice and freely, I could spin it by hand with all pistons in (no compression) no binding or nothing.
Got it all together, and after about 10-15 seconds of cranking, it locked up. Tore the pan off and the wrist pins are seized in the pistons! Like 3 or 4 of them. Some on each side. But no pattern. Never seen anything like this! Another engine builder looked at it and can’t figure it out either.
Anybody have any idea what could have gone wrong? I’m open to the idea that my rods are on the wrong side? But it just doesn’t seem that way. If switched them, the offset would be too great I think and would bind even tryin to turn by hand.
Anybody have a way of knowing for sure which way the rods are supposed to face?
You don’t have to reply saying I need to mark them. I know that, like I said, a miscommunication. I’ve done hemis before. Looking for some help here, I’m tearing it all back apart now, but want to do it right this time lol. Thanks!